<form method="post" action="index.php?op=avalicao_ret" enctype="multipart/form-data">
    <p>
        <input type="file" name="retornos[]" multiple="multiple" id="retornos" class="input text-input"/>
        <button class="btn submit green3-grad-back"> 
            Submeter <img src="<?php echo GRID_ICONS."upload.png";?>" style="vertical-align: middle;">
        </button>
    </p>
    <p class="title-form v-separator"> Arquivos Selecionados </p>
    <div id="list-files">
        Nenhum arquivo selecionado
    </div>
</form>
<style>
form{
    width: 50%;
}
form button.submit {
    float: right;
}
#list-files {
    padding: 10px;
    box-shadow: inset 0 0 5px lightgray;
    font-size: 10pt;
    max-height: 50%;
    overflow-y: auto;
    text-align: center;
}
.entry-list{
    padding: 10px;
    box-shadow: 0 0 3px lightgray;
    display: inline-block;
    margin: 5px;
}
</style>
<script>
var list = $("#list-files");
$('#retornos').change(function(event){
    list.html("");
    var files = event.target.files;
    for(var i = 0, l = files.length; i < l; i++){
        list.append('<div class=\'entry-list\'>' + files[i].name + '</div>');
    }
});
</script>